汽车用HAl62-4-3-0.1同步器齿环的研制

【作者】 马斌；

【导师】 张胜华；

【作者基本信息】 中南大学 ， 材料加工工程， 2002， 硕士

【摘要】 通过调整合金的成分，配制了添加Al、Mn、Si、Fe和Re的复杂黄铜合金，比较两种不同的铸造工艺，选取经电磁搅拌的铸坯，在GLEEBLE-1500热模拟机上模拟合金的高温屈服强度σ_s，并对合金进行热处理正交实验，用金相显微镜、扫描电镜观察和透射电镜分析合金不同状态下的显微组织和结构，并借助HP-134工作站和相应的软件模拟不同加工工艺下的复杂黄铜合金的锻压变形过程。研究结果表明：Al含量可以改变复杂黄铜中α相和β相的体积百分数，提高合金的硬度，改善合金的耐磨性，但Al含量一般不能超过3.5％，否则会出现有害的γ相，降低合金韵性能；添加微量元素Mn、Fe、Si可在复杂黄铜合金晶内形成Mn₅Si₃、Fe₃Si、Fe₃Al硬质相，不但促进非均匀形核，使合金晶粒细化，而且它们弥散分布在基体表面，使合金磨损时产生三体研磨，提高合金的耐磨性；稀土是一种很好的细化剂，但熔炼时必须保证稀土的含量，一般不高于0.1％，否则会出现有害的富稀土相，降低合金的性能；对于复杂黄铜来说，淬火温度、保温时间、时效温度对合金的硬度影响显著，因此要合理的控制热处理工艺；耐磨性并不是与合金的硬度成正比，而是存在一个最佳耐磨值。实验证明：少量的α相+基体相β相+硬质颗粒相（Mn₅Si₃、Fe₃Si、Fe₃Al、）是理想的耐磨组织；计算机模拟的结果表明：铸态和挤压态合金在锻压时不同的是，铸态合金所需的锻压力比较小。合金在高温下塑性极好，但由于锭坯较小，合金降温极快，所以建议用高速锻压。更多还原

【Abstract】 In this paper,high-tensile and wear resistant brasses added Al> Mn^ Fe^ Si and Re were prepared by adjusting the component of the alloys.The mechanical properties of this material at various high temperature were tested during the process of simulating .The microstructure of the alloys in different conditions were observed by optical microscope ,SEM and TEM. In this paper, the DEFORM?program was used to simulate the forging of special brasses.The results are shown: The percentage of a and P phase were adjusted by the content of Al,which must be controlled less 3.5%.The phase of Mn5Si3, Fe3Si, Fe3Al may not only decrease the grains size but also improve the wear resistance by distributing dispersed.The content of RE must be constrolled accurately less 0.1% lest forming the harmful phase of RE decreasing the properties of the alloys.Wear resistence was not proportal to the hardness ,In fact, little a phase and 3 phase adding some partical phase was a peferct structure of wear resistence. The plastic of high-tensile brasses was very good ,when being forged ,the speed of forging must be quick.更多还原